They are currently in slightly larger groups but can be rehomed in smaller groups of threes or four. Mice are very social animals so they need to stay with friends. They are friendly, easy to handle and are happy to come out and explore the world around them.
Mice are very small and can be very active, but tend to prefer the night life. They need lots of hiding spots and enrichment, and will build small nests out of their bedding. The more mice you have in one cage, the more you will need to clean it, so keeping 3-4 mice in one cage means you should be cleaning them once a week or so. They need a house that is ideally has a tank mesh lid or plastic cage with no bars to avoid any escapees. Mice require fresh water and food daily. They should be fed mice nuggets, which may look bland, but are generally better than mixed food or muesli as mice tend to be selective and may not get all the nutrition they need!